In a small bowl, whisk the apple cider vinegar, soy sauce or tamari, water, grated ginger, and sesame oil. Place the tempeh in a small casserole dish or wide, shallow bowl, and pour the marinade over the tempeh. Refrigerate and allow to marinate at least 2-3 hours.
In a medium mixing bowl, whisk together the miso, Dijon mustard, olive oil, lemon juice, garlic, and maple syrup. Season to taste with salt and pepper, and set aside.
Heat the coconut oil in a large skillet over medium-high heat. Pan-fry the marinated tempeh, cooking each side 3-4 minutes, until golden-brown and crispy. Remove from heat and set aside.
Bring a small pot of water to a boil. Cook the snow peas in boiling water for just under 30 seconds. Drain in a colander and rinse under cold water immediately to stop the cooking process. Slice into halves or thirds.
In a large serving bowl, combine the snow peas, cabbage, carrot, mizuna, green onions, and cilantro. Dress with the miso-mustard dressing, and toss to coat. Serve immediately, topped with the tempeh.